While the versions have the same version number apt detects them as different and prefers to download and install the version coming from a repository over the locally installed one.

This is to help with rebuilds of packages with the same version number - it's discouraged, but not too uncommon.

That they are different is concluded from different dependencies and similar stuff. I can tell you what exactly is the bugger if you post the the output of 'apt-cache show opera -a'. So, until further notice, this is a feature, not a bug.

_________________MfG. DonKult
"I never make stupid mistakes. Only very, very clever ones." ~ The Doctor